A-Shell Reference

Symbol

Name

Description

'

apostrophe

May appear in variable or defined symbol names (after first character).

-

minus sign

Subtraction operator, or unary negative operator.

!

exclamation point

Start of comment; anything to right is ignored by compiler.

"

quote

Used to enclose literal strings. Two quotes in succession ( "" ) translates to a single literal quote.

#

pound sign, aka hash or octothorp

Not equals comparison operator, equivalent to <>. Also used in Explicit Plus Operators and Explicit Comparison Operators.

$

dollar sign

As a suffix on a variable or function name, indicates string type. Also used in Explicit Plus Operators and Explicit Comparison Operators.

%

percent sign

Not used.

&

ampersand

Line continuation (if last character on line, not counting comments to the right). Also used to indicate "and" in Shortcut Operators.

()

open and closed parentheses

Used to override operator precedence in expressions, to enclose function and procedure argument lists, with array variables to specify the subscripts, and with ordered maps to specify the map key. An empty pair of parentheses on the end of an array or ordered map refers to the array or map as a whole.

*

asterisk

Multiplication operator.

,

comma

Used to separate parameters (XCALLs, function calls) or expressions within a PRINT statement.

.

period

Used as a prefix for some keywords to distinguish them from ordinary variables. Also used to join structure and member names (e.g. cust.name). See Dot Functions, Dot Variables, MLIST Dot-tokens, Special ORDMAP Functions.

/

forward slash

Division operator.

:

colon

Separates multiple statements on one source line. Also required as last character of a label.

;

semi-colon

Used at the end of a PRINT statement to suppress the output of CR or CRLF line terminator

@

at sign

Used in overlay declarations. See MAP Statements, Dynamic Overlays.

[]

square brackets

Substring Operator.

\

backslash

Not used.

^

caret

Exponentiation operator.

_

underscore

May appear in variable or defined symbol names (after first character).

`

grave accent

Not used.

{}

squiggly brackets

Not used.

|

vertical bar or pipe

Used to indicate "or" Shortcut Operators.

~

tilde

Not used

+

plus sign

Numeric addition or string concatenation; see Overloaded Plus Operator, Explicit Plus Operators.

<>

angle brackets

Used individually as greater-than or less-than operators, or together as the not-equal comparison operator.

=

equal sign

Assignment or comparison operator. Also see Shortcut Operators.

LF

line feed

Implicit termination of a statement, usually as the second character in the CRLF pair.

0-9

numeric digits

May appear in numeric literals or variable or defined symbol names (after first character)

A-Z,
a-z

alphabetic
characters

May appear in variable or defined symbol names (case sensitive unless compiled with /CI switch); or in keywords.

ASCII

1-31

control characters

Used only in literal strings. Note that CR, LF may require encoding using the chr(#) function to avoid syntax issues with compiler.

ASCII 128-255

upper range, (high bit set); accented characters, etc.

Used only in literal strings.